In January 2006, geneticists at Trinity College, Dublin suggested that Niall may have been the most fecund male in Irish history. The findings of the study showed that within the north-west of Ireland as many as 21% of men (8% in the general male population) were concluded to have a common male-line ancestor who lived roughly 1,700 years ago. The geneticists estimated that there are about 2-3 million males alive today who descend in the male-line from Niall.[14] However, more recently some reservations have been expressed, as the subclade, which is defined by the presence of the marker R-M222, is found in a belt from Northern Ireland across southern Scotland and is not exclusively associated with the Uí Néill. It is now more commonly referred to as the Northwest Irish/Lowland Scots variety.[15]